The rabid fox that attacked a dog this spring near Magdalena was carrying a variant of the disease that spread from Arizona, according to the New Mexico Department of Health, which strongly urges residents to get their pets and valuable livestock vaccinated.

The DOH confirmed the fox had rabies within days of the incident. Further testing at the Centers for Disease Control and Prevention in Atlanta shows the fox had the Arizona gray fox rabies variant, Dr. Paul Ettestad, DOH state public health veterinarian, said during an interview May 3.

Ettestad said no special vaccines are necessary for this variant of the disease.

“Luckily the rabies vaccines we have are effective against all different types of rabies,” he said.

The infected fox attacked a young dog at a home about a mile south of Magdalena on March 23, according to a March 28 DOH news release. The dog was euthanized because it hadn’t received a rabies vaccination. No people, other pets or livestock were known to have been bitten by the rabid fox. Prior to the March 23 incident, the last confirmed animal rabies cases in Socorro County were a calf and a bat, both in 2009.

Ettestad said the DOH sent part of the fox’s brain to the CDC, which did variant typing and found the rabies virus to be the Arizona gray fox variant. He explained the disease has slightly different variants among the different species that carry it.

Ettestad said this rabies variant was first seen in New Mexico in 2007 in the area of Glenwood, which is in southern Catron County near the Arizona border.

“The case you guys had (by Magdalena) … is probably the farthest north and east that we’ve found it, so the concern here is that this is moving from fox to fox,” Ettestad said about the gray fox variant. “And so, since you’ve had one case, there potentially could be more because there’s probably more foxes out there that have been exposed.

“So that’s what makes it really important that people get their dogs and cats vaccinated, and even consider getting some of their livestock — if they have a valuable horse or valuable bull — getting that vaccinated against rabies also.”

Ettestad said rabid foxes occasionally attack humans, but a person is far more likely to be exposed to the disease through an unvaccinated pet that has encountered an infected fox. He noted many people in rural areas don’t think they need to vaccinate their pets against rabies, but they definitely should.

“This is especially important now, with these foxes out there with rabies, for them to make sure their animals are vaccinated,” Ettestad said.

If a pet hasn’t been vaccinated for a long time, Ettestad recommended the pet owner call their veterinarian and see if their vaccinations are overdue. He said even if the shots are overdue, typically only one shot is needed to boost the animal’s immune system.

Ettestad said rabies is invariably fatal, and symptoms may take one to three months to manifest. In that time, many people could be exposed to an infected animal without realizing it.

Ettestad said larger animals like horses or cattle may stagger and exhibit poor coordination, as well as difficulty swallowing. He recommended animals with those symptoms be examined by a veterinarian.

He said a dog that has been infected will first show significant behavioral changes; it may become restless or apprehensive, and perhaps more aggressive. He said a friendly dog may become withdrawn and irritable. Excitable dogs may become much more docile. He noted infected dogs might bite or snap at anything — animals, people or even inanimate objects.

“They’ll just snap at the air almost,” Ettestad said.

He added infected dogs are often observed licking or chewing themselves at the site they were bitten.

As the disease progresses, Ettestad said the animal may develop paralysis, especially in the throat and jaw muscles. They become disoriented and uncoordinated, staggering when they walk.

“Then typically they’ll start to have seizures and die,” he said. “So it’s pretty much a 100 percent fatal disease — but the vaccine is very good at protecting animals.”

The city of Socorro sponsors a free rabies clinic for dogs and cats this Saturday from 8 to 11 a.m. on the plaza. Terry Tadano, director of the Socorro Chamber of Commerce, said 140 rabies shots were administered free of charge during the clinic the city sponsored April 20.

The Ark of Socorro will administer shots this Saturday. Animal Haven Veterinary Clinic administered the shots at the April clinic.

Tadano said the city pays for the rabies vaccinations, but the veterinarians donate their time. If pet owners want to inoculate against parvo, distemper or other diseases in addition to rabies, Tadano said they need only pay the difference. He said the city will also provide free dog licenses at the clinic to pet owners who have their dogs vaccinated for rabies.

“The city is scrounging up the money to get this done,” Tadano said.

Tadano explained the city went a little over what it had budgeted for the free clinics last summer, and these spring 2013 clinics fall within the same fiscal year, which ends in June.